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There are way too many changes to list here but the following is a small snippet of changes, see Dulfy link for more information:
Tempesthttp://dulfy.net/2015/08/17/gw2-tempest-changes-based-on-bwe-feedback/All overloads are at least 20% stronger than before.Overload Water – Increased the amount that healing power affects pulsed healing by 400%. Increased the final heal value by 50%.Several warhorn skills damage has been increased by at least 20%.
Dragonhunterhttp://dulfy.net/2015/08/17/gw2-dragonhunter-changes-based-on-bwe-feedback/F1 Spear of Justice: Increased range from 900 to 1,200. Increased impact damage by 20%.F2 Wings of Resolve: Increased heal value by up to 50%.Traps were buffed and traits were buffed as well.